A Pyramid power supply should work as well as most others, it's a common choice. The thing with any power supply is to not over load the thing or expect it to do something it wasn't designed for. Power supplies have two ratings, 'CCS', or continuous current supply, and 'ICS', or intermittent current supply. The ICS rating is what you see advertised in most cases, and it's only good for short periods of time, or surges. The CCS is what the thing will deliver all the time. The CCS is usually something like 1/2 to 2/3rds of the ICS rating. It's never a good idea to run something at max all the time, so some extra 'head-room' is always nice to have. (That CCS/ICS ratios are only rough estimates! Read the specs for any particular power supply.)
It doesn't matter if the radio is VHF/UHF or HF, it only matters what current is normally requires to operate. If it requires 20 amps then something with a 25 - 30 amp CCS rating should do just dandy. If you think you may run more than one device from that power supply, add up the current ratings for all the devices being powered. That total is the minimum for the size of power supply required.
There are no 'iron-clad' guarantees. The next Cadillac or Mercedes you drive off the showroom floor may drop dead after making the first corner turn. Same with power supplies. The best protection for the devices hooked to that power supply is a properly sized fuse (and not asking too much of the power supply?). In general, a 'Pyramid', or 'Astron', or any typical manufacturer's power supply should last for as long as is 'normal'. (No idea what's a 'normal' period of time, sorry.)
- 'Doc